Canadian marijuana producer Tilray Inc. says it has received approval from the U.S. Drug Enforcement Administration agency to export a medical cannabis product south of the border for use in a clinical trial.

The company and a researcher at the University of California San Diego believe this is the first export of a cannabis product from a Canadian company to the U.S., where marijuana is still illegal at the federal level.

Tilray will be exporting capsules containing a formulation with two active ingredients extracted from the cannabis plant for a clinical trial examining the drug as a potential treatment for adults with essential tremor.

The formulation will contain cannabidiol and tetrahydrocannabinol, better known as CBD and THC, and will be used in a trial scheduled to begin in early 2019.

UC San Diego’s Dr. Fatta Nahab said he believes this product has not been imported from Canada into the U.S. before.

While several states have legalized cannabis for medical or recreational use, marijuana remains illegal under U.S. federal law.